Food sources of vitamin B12
In surveys of typical diets the remarkable difference behveen diets adequate and poor in the vitamin BI2 content emphasizes the importance ofthe contribution made by meats and other animal products to the BI2 intake. Dietary deficiencies of vi tamin B 12 have been found among vegans when no animal foods are consumed.
A severe case of congeni tal vitamin B 12 deficiency has been reported recently in a breast-fed infant whose mother had adhered to a strict vegetarian diet for 8 years.
Seafoods, meats, eggs, and dairy products are all good sources of vitamin B12 Foods of vegetable origin do not contain vitamin BI2 unless it is added in enrichment. Contributions by bacterial contamination of food and water and, perhaps, by limited synthesis in the small intestine, may be responsible for the rarity of vitamin BI2 deficiency in vegetarians in developing countries.
